US4994716A - Circuit arrangement for starting and operating gas discharge lamps - Google Patents

Circuit arrangement for starting and operating gas discharge lamps Download PDF

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Publication number
US4994716A
US4994716A US06/900,191 US90019186A US4994716A US 4994716 A US4994716 A US 4994716A US 90019186 A US90019186 A US 90019186A US 4994716 A US4994716 A US 4994716A
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US
United States
Prior art keywords
lamp
circuit
capacitor
voltage
current
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Expired - Fee Related
Application number
US06/900,191
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English (en)
Inventor
Hans-Gunther Ganser
Ralf Schafer
Hans-Peter Stormberg
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US Philips Corp
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US Philips Corp
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Assigned to U.S. PHILIPS CORPORATION reassignment U.S. PHILIPS CORPORATION ASSIGNMENT OF ASSIGNORS INTEREST. Assignors: GANSER, HANS-GUNTHER, SCHAFER, RALF, STORMBERG, HANS-PETER
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    • H—ELECTRICITY
    • H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
    • H05B—ELECTRIC HEATING; ELECTRIC LIGHT SOURCES NOT OTHERWISE PROVIDED FOR; CIRCUIT ARRANGEMENTS FOR ELECTRIC LIGHT SOURCES, IN GENERAL
    • H05B41/00—Circuit arrangements or apparatus for igniting or operating discharge lamps
    • H05B41/14—Circuit arrangements
    • H05B41/36—Controlling
    • H05B41/38—Controlling the intensity of light
    • H05B41/382—Controlling the intensity of light during the transitional start-up phase
    • H05B41/384—Controlling the intensity of light during the transitional start-up phase in case of hot-restriking
    • H—ELECTRICITY
    • H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
    • H05B—ELECTRIC HEATING; ELECTRIC LIGHT SOURCES NOT OTHERWISE PROVIDED FOR; CIRCUIT ARRANGEMENTS FOR ELECTRIC LIGHT SOURCES, IN GENERAL
    • H05B41/00—Circuit arrangements or apparatus for igniting or operating discharge lamps
    • H05B41/14—Circuit arrangements
    • H05B41/16—Circuit arrangements in which the lamp is fed by dc or by low-frequency ac, e.g. by 50 cycles/sec ac, or with network frequencies
    • H05B41/18—Circuit arrangements in which the lamp is fed by dc or by low-frequency ac, e.g. by 50 cycles/sec ac, or with network frequencies having a starting switch
    • H05B41/19—Circuit arrangements in which the lamp is fed by dc or by low-frequency ac, e.g. by 50 cycles/sec ac, or with network frequencies having a starting switch for lamps having an auxiliary starting electrode
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02B—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO BUILDINGS, e.g. HOUSING, HOUSE APPLIANCES OR RELATED END-USER APPLICATIONS
    • Y02B20/00—Energy efficient lighting technologies, e.g. halogen lamps or gas discharge lamps
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10S—TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10S315/00—Electric lamp and discharge devices: systems
    • Y10S315/04—Dimming circuit for fluorescent lamps
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10S—TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10S315/00—Electric lamp and discharge devices: systems
    • Y10S315/07—Starting and control circuits for gas discharge lamp using transistors

Definitions

  • This invention relates to a circuit arrangement for starting and operating a gas discharge lamp with a current of higher frequency, and provided with an electronic ballast unit which is to be connected to an input d.c. voltage source and comprises an electronic switching element which is controlled by a control device and is connected in series with an inductive element which is acted upon by the lamp current and from which a voltage can be derived, which is fed as a d.c. supply voltage to the control device through a rectifier and a smoothing capacitor.
  • a current of higher frequency is to be understood to mean an alternating current having a frequency between 10 and 500 kHz, preferably between 20 and 150 kHz.
  • an object of the invention is to provide, in a circuit arrangement for starting and operating gas discharge lamps comprising an electronic ballast unit, a d.c. voltage supply for its control device, which is constructed as simply as possible and so as to be loss-free and which may be combined with other necessary functions of the ballast unit. Furthermore, the circuit arrangement should provide a reliable start even with lamps igniting only with difficulty.
  • this object is achieved in a circuit arrangement of the kind mentioned in the opening paragraph in that the first connection (terminal) of the smoothing capacitor is connected through a first ohmic resistor to a first terminal of the input direct voltage source and its second connection (terminal) is connected through the lamp to a second terminal of the input direct voltage source.
  • the lamp can be traversed, via a current circuit comprising the smoothing capacitor and the first ohmic resistor, by an additional current for normal current flow through the actual electronic ballast unit.
  • This current facilitates the ignition of the lamp, more particularly the ignition of a still hot lamp, and at the same time charges the smoothing capacitor to the d.c. voltage level required for driving the switching element.
  • a voltage-stabilizing element is connected parallel to the smoothing capacitor.
  • the ohmic resistor connected in series with the smoothing capacitor limits the additional flow of current through the lamp. It may be advantageous that a controllable semiconductor switch is connected in series with the first ohmic resistor and the smoothing capacitor. The controllable semiconductor switch serves to interrupt the current through the first ohmic resistor after the lamp has started. Thus, losses in the first ohmic resistor are avoided.
  • the controllable semiconductor switch is a first switching transistor.
  • This switching transistor can be switched on and off in a simple manner in that its collector-base path is shunted by a second ohmic resistor and its emitter-base path is shunted by a second switching transistor, whose base is connected to the end facing the rectifier of a current-limiting resistor arranged between the rectifier and the smoothing capacitor.
  • the second switching transistor becomes conductive due to the voltage drop at the current-limiting resistor.
  • the first switching transistor again becomes high-ohmic and thus interrupts the additional flow of current.
  • a voltage-dependent threshold element for example a Zener diode, a diac or a sidac, as a result of which the second switching transistor becomes conductive only when the voltage drop exceeds the threshold voltage of the threshold element.
  • the starting behaviour of the lamp may be improved if the additional flow of current is still maintained for some time after the starting operation.
  • This can be achieved in that an RC combination is connected to the current-limiting resistor and to the base of the second switching transistor so that its base voltage can increase only with delay.
  • the required first switching transistor must be comparatively large and expensive. Therefore, it is advantageous to use instead of the first switching transistor a less expensive and smaller transistor or triac as the controllable semiconductor switch for interrupting the additional flow of current.
  • the thyristor can then be switched on and off in a simple manner by a circuit arrangement in which the series-combination comprising the thyristor or triac and the smoothing capacitor is shunted by a voltage divider which comprises two subresistors and of which the junction point of the two subresistors is connected through a voltagedependent threshold element to the control electrode of the thyristor or triac.
  • the voltage-dependent threshold element again may be a Zener diode, a diac or a sidac.
  • This circuit arrangement affords the advantage that an ignition of the thyristor or triac takes place already when the smoothing capacitor has not yet been charged and the ignition of the thyristor or triac is automatically interrupted when the voltage at the smoothing capacitor reaches a given value.
  • an ignition circuit comprising elements supplying an ignition pulse to the lamp or its external ignition electrode can be connected parallel to the lamp. At the same time, these elements permit, when the lamp is not yet ionized, a flow of current for charging the smoothing capacitor.
  • thyristors With the use of thyristors (triacs), a problem can occur in that a synchronization between the ignition of the thyristor (triac) and the ionization of the lamp by a lamp ignition circuit need not exist. Therefore, it may occur that upon ionization of the lamp, the thyristor has already become non-conductive again because a sufficient flow of current was not possible through the lamp not yet ionized. According to a further embodiment of the invention, this can be avoided in that by means of a third ohmic resistor, a further current path parallel to the lamp is formed, which permits that, even when the lamp is not ionized, a current to flow through the thyristor (triac) which lies above its hold current. Thus, the thyristor (triac) remains conducting until the lamp is ionized; the actual additional current can then flow through the thyristor (triac) and the lamp and consequently can ensure a reliable ignition of the lamp
  • FIG. 1 shows a circuit arrangement for starting and operating a gas discharge lamp having a down converter controlled via a control device.
  • FIG. 2 shows a modified circuit arrangement of this, kind.
  • a and B designate input terminals for connection to an alternating voltage mains of, for example, 220 V, 50 Hz.
  • a full-wave rectifier 1 comprising four diodes is connected to these input terminals A and B, as the case may be through a high-frequency filter (not shown), while a charging capacitor 2 is connected parallel to the output of this rectifier.
  • a down converter comprising an electronic switching element 3, for example a switching transistor, a choke coil 4, a gas discharge lamp 5 and a fly-wheel diode 6 is connected to the output of the full-wave rectifier 1.
  • the charging capacitor 2 constitutes an input voltage source and serves inter alia to facilitate the re-ignition of the lamp 5.
  • the choke coil 4 then constitutes an inductive element acted upon by the lamp current in the connected state of the lamp. Furthermore, a measuring resistor 7 serving as a current sensor is inserted into the lamp circuit and at this resistor is derived an actual voltage which is proportional to the instantaneous actual lamp current and which is fed to the input C of a control device 8. In known manner the control device 8 causes the lamp current to follow a nominal signal to be applied to the input D of the control device 8.
  • the current derived from the alternating voltage mains should vary as sinusoidally as possible.
  • the audio-frequency signal occurring at the output E of the control device 8 switches the electronic switching element 3 into the conducting and the non-conducting state, respectively.
  • the terminal F of the switching device 8 is connected to ground. Through the terminal G, a supply direct voltage is supplied to the control device 8.
  • An ignition circuit comprising a charging resistor 9, a pulse capacitor 10, a sidac switching element 11 and an ignition transformer 12 is connected parallel to the lamp 5.
  • the pulse capacitor 10 is charged to the voltage applied across the lamp 5.
  • this switching element becomes conductive so that the pulse capacitor 10 is discharged through the primary winding of the ignition transformer 12 and then produces in its secondary winding a voltage pulse of a few kV, which is fed to a starting electrode H of the lamp 5.
  • the sidac switching element becomes high-ohmic again.
  • the d.c. supply voltage (for example +10 V) for the control device 8 and for major switching transistor 3 is produced from a tapping 13 of the choke coil 4.
  • the audio-frequency voltage derived at the said choke coil 4 is then rectified by means of a rectifier diode 14 and is supplied via a current-limiting resistor 15 to a smoothing capacitor 16, being parallel connected for voltage limitation by a Zener diode 17 as a voltage-stabilizing element.
  • the charging voltage of the smoothing capacitor 16 is supplied to the control device 8 through its terminals F and G as a d.c. supply voltage.
  • the high-frequency voltage is then produced at the tapping 13, however, only when the switching transistor 3 switches already, i.e. when a d.c. supply voltage is already present.
  • the smoothing capacitor 16 is connected through a first ohmic resistor 18 and a first switching transistor 19 to the first terminal of the input direct voltage source 2 and is connected through the choke coil 4 and the lamp 5 ionized by the ignition circuit and through the resistor 9, the capacitor 10 and the ignition transformer 12, respectively, to the second terminal of the input direct voltage source 2.
  • the capacitor 16 is consequently charged by the rectified mains voltage. A reliable ignition of the lamp is obtained by the additional charging current then flowing through the lamp.
  • the first switching transistor 19, constituting the controllable semiconductor switch is set to the conducting state by a second ohmic resistor 20 connected across the collector-base path.
  • the control device 8 and hence the switching transistor 3 start to operate, as a result of which the said high-frequency voltage occurs at the tapping 13 of the choke coil 4 and hence the smoothing capacitor 16 is normally charged.
  • a voltage drop is then obtained at the current-limiting resistor 15 and this voltage drop acts upon the base of a second switching transistor 21 shunting the emitter-base path of the first switching transistor 19.
  • the second switching transistor 21 becomes conductive and hence the first switching transistor 19 is again switched to the high-ohmic state so that the additional charging current circuit for the smoothing capacitor 16, which is now no longer necessary, is interrupted.
  • a voltage-dependent threshold element in the form of a Zener diode 22 and a resistor 23 are connected between the current-limiting resistor 15 and the base of the switching transistor 21.
  • Resistor 23 and capacitor 24 forms an RC combination.
  • the Zener diode 22 ensures that the base of the second switching transistor 21 is not driven until the voltage drop at the current-limiting resistor 15 lies above the Zener voltage of the Zener diode 22, as a result of which it is ensured that a sufficient current can flow from the choke coil 4 to the smoothing capacitor 16.
  • the additional current circuit is interrupted so as to be delayed by the time constant R 23 .C 24 because the voltage increase at the base of the second switching transistor 21 takes place with a corresponding delay.
  • the additional current flow through the lamp 5 is maintained during the first mains half cycles succeeding the ionization of the lamp 5, which leads to an improvement of its ignition and starting behaviour.
  • FIG. 2 shows a circuit arrangement in which inexpensive thyristors or triacs are used which can be driven with low losses, but nevertheless pass high currents.
  • the electronic ballast unit is again the down converter circuit known from FIG.
  • a superheterodyne igniter comprising an ignition transformer 12, a charging resistor 9, a sidac switching element 11 and a pulse capacitor 10 as well as a high-frequency return capacitor 25 is used for ignition of the lamp 5 (See DE -OS 3108547).
  • the smoothing capacitor 16 is fed from the choke coil 4 in the same manner as in the circuit arrangement shown in FIG. 1.
  • the smoothing capacitor 16 is charged through the first ohmic resistor 18, a thyristor 26 (or triac) as well as the choke coil 4, the ignition transformer 12 and the lamp 5 ionized by the ignition circuit.
  • the thyristor 26 is ignited by means of a voltage divider comprising two subresistors 27,28 and a diac 29 as a voltage-dependent threshold element, which breaks down and initiates through a limiting resistor 30 the ignition of the thyristor 26 as soon as a voltage above the breakdown voltage of the diac 29, of about 30 V is applied between its cathode and its control electrode.
  • the voltage divider resistors 27,28 are constructed so that this always occurs when the smoothing capacitor 16 is still uncharged.
  • the smoothing capacitor 16 When the smoothing capacitor 16 is charged however, the latter builds up a counter voltage of, for example, about 10 V, which reduces the voltage between cathode and control electrode of the thyristor 26 to such an extent that the diac 29 no longer breaks down and hence no longer causes the thyristor 26 to ignite.
  • a further capacitor 31 parallel to the subresistor 28.
  • Transistor 3 IRF 730 of International Rectifier
  • transistor 21 BC 107 of Valvo
  • diode 14 BAV21 of Valvo
  • Zener diode 17 BZV85/C10 of Valvo
  • Zener diode 22 BZX79/C3V6 of Valvo;
  • resistor 9 100 k ⁇
  • resistor 15 1 k ⁇
  • resistor 18 2.2 k ⁇
  • resistor 20 68 k ⁇
  • resistor 23 3.9 k ⁇
  • resistor 7 1 k ⁇
  • Thyristor 26 BT149 or BT151 of Valvo;
  • resistor 18 290 ⁇ ;
  • resistor 27 680 k ⁇
  • resistor 28 120 k ⁇
  • resistor 34 25 k ⁇
  • resistor 30 18 ⁇ ;
  • resistor 33 470 ⁇ .
  • the electronic ballast unit need not necessarily be a down converter, but may also be in the form of a fly-back converter, a bridge or half bridge circuit or a resonance converter.
  • the choke tapping 13 the whole choke 4 or a secondary winding provided on the choke may be used.
  • the rectifier diode 14 a bridge rectifier may then be used.

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  • Circuit Arrangements For Discharge Lamps (AREA)
US06/900,191 1985-08-28 1986-08-25 Circuit arrangement for starting and operating gas discharge lamps Expired - Fee Related US4994716A (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE3530638 1985-08-28
DE19853530638 DE3530638A1 (de) 1985-08-28 1985-08-28 Schaltungsanordnung zum starten und betrieb von gasentladungslampen

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US4994716A true US4994716A (en) 1991-02-19

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US06/900,191 Expired - Fee Related US4994716A (en) 1985-08-28 1986-08-25 Circuit arrangement for starting and operating gas discharge lamps

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US (1) US4994716A (fr)
EP (1) EP0212740A3 (fr)
JP (1) JPS6251194A (fr)
DE (1) DE3530638A1 (fr)

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5291100A (en) * 1991-01-09 1994-03-01 Welch Allyn, Inc. Low watt metal halide lamp apparatus
US5319286A (en) * 1992-10-29 1994-06-07 North American Philips Corporation Ignition scheme for a high intensity discharge ballast
US6184635B1 (en) * 1999-05-20 2001-02-06 Patent-Treuhand-Gesellschaft Fuer Elektrische Gluehlampen Mbh Circuit arrangement for starting and for operating high-pressure lamps
US20030001515A1 (en) * 2001-06-29 2003-01-02 Ushiodenki Kabushiki Kaisha Light source device
US20100277178A1 (en) * 2009-04-30 2010-11-04 Osram Gesellschaft Mit Beschraenkter Haftung Method for ascertaining a type of a gas discharge lamp and electronic ballast for operating at least two different types of gas discharge lamps

Families Citing this family (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE3729383A1 (de) * 1987-09-03 1989-03-16 Philips Patentverwaltung Schaltungsanordnung zum starten einer hochdruckgasentladungslampe
US8956421B2 (en) 2007-02-06 2015-02-17 Deka Products Limited Partnership Dynamic support apparatus and system
DE202005003632U1 (de) * 2005-03-03 2006-07-13 Bag Electronics Gmbh Zündschaltungsanordnung mit erhöhter Ausfallsicherheit

Citations (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3878429A (en) * 1968-11-14 1975-04-15 Hiroshi Iwata Electronic flash device with automatic light control
US3896333A (en) * 1972-05-10 1975-07-22 Canon Kk Electronic flash device
GB1528033A (en) * 1974-10-21 1978-10-11 Gen Electric Ballast for an arc discharge lamp
US4194143A (en) * 1977-10-27 1980-03-18 Hoffmann-La Roche Inc. Power supply for flash lamp
US4316124A (en) * 1978-10-02 1982-02-16 U.S. Philips Corporation Mixed light arrangement
US4447759A (en) * 1980-12-16 1984-05-08 U.S. Philips Corporation Starter for igniting an electric discharge tube
US4520295A (en) * 1981-11-09 1985-05-28 U.S. Philips Corporation Step-wise dimmer control circuit for a discharge lamp
US4539513A (en) * 1982-12-11 1985-09-03 U.S. Philips Corporation Circuit arrangement for starting and operating a high-pressure gas discharge lamp
US4663569A (en) * 1985-09-26 1987-05-05 General Electric Company Energy management/dimming system and control
JPH0274801A (ja) * 1988-07-25 1990-03-14 Unisearch Ltd 光学的結像と位置決めシステム

Family Cites Families (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3771007A (en) * 1970-10-15 1973-11-06 Gen Electric High intensity lamp apparatus and method of operation thereof
US3944876A (en) * 1974-09-30 1976-03-16 Chadwick-Helmuth Company, Inc. Rapid starting of gas discharge lamps

Patent Citations (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3878429A (en) * 1968-11-14 1975-04-15 Hiroshi Iwata Electronic flash device with automatic light control
US3896333A (en) * 1972-05-10 1975-07-22 Canon Kk Electronic flash device
GB1528033A (en) * 1974-10-21 1978-10-11 Gen Electric Ballast for an arc discharge lamp
US4194143A (en) * 1977-10-27 1980-03-18 Hoffmann-La Roche Inc. Power supply for flash lamp
US4316124A (en) * 1978-10-02 1982-02-16 U.S. Philips Corporation Mixed light arrangement
US4447759A (en) * 1980-12-16 1984-05-08 U.S. Philips Corporation Starter for igniting an electric discharge tube
US4520295A (en) * 1981-11-09 1985-05-28 U.S. Philips Corporation Step-wise dimmer control circuit for a discharge lamp
US4539513A (en) * 1982-12-11 1985-09-03 U.S. Philips Corporation Circuit arrangement for starting and operating a high-pressure gas discharge lamp
US4663569A (en) * 1985-09-26 1987-05-05 General Electric Company Energy management/dimming system and control
JPH0274801A (ja) * 1988-07-25 1990-03-14 Unisearch Ltd 光学的結像と位置決めシステム

Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5291100A (en) * 1991-01-09 1994-03-01 Welch Allyn, Inc. Low watt metal halide lamp apparatus
US5319286A (en) * 1992-10-29 1994-06-07 North American Philips Corporation Ignition scheme for a high intensity discharge ballast
US6184635B1 (en) * 1999-05-20 2001-02-06 Patent-Treuhand-Gesellschaft Fuer Elektrische Gluehlampen Mbh Circuit arrangement for starting and for operating high-pressure lamps
US20030001515A1 (en) * 2001-06-29 2003-01-02 Ushiodenki Kabushiki Kaisha Light source device
US6734643B2 (en) 2001-06-29 2004-05-11 Ushiodenki Kabushiki Kaisha Light source device
US20100277178A1 (en) * 2009-04-30 2010-11-04 Osram Gesellschaft Mit Beschraenkter Haftung Method for ascertaining a type of a gas discharge lamp and electronic ballast for operating at least two different types of gas discharge lamps
US8754652B2 (en) * 2009-04-30 2014-06-17 Osram Gesellschaft Mit Beschraenkter Haftung Method for ascertaining a type of a gas discharge lamp and electronic ballast for operating at least two different types of gas discharge lamps

Also Published As

Publication number Publication date
DE3530638A1 (de) 1987-03-05
EP0212740A2 (fr) 1987-03-04
JPS6251194A (ja) 1987-03-05
EP0212740A3 (fr) 1987-09-09

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